The Cyberspace Administration of China released draft rules on Sunday that would require firms to undergo a cyber security review before going public in Hong Kong if it implicates national security, threatening a recent shift as internet companies seek to list in the territory. The powerful data watchdog launched a probe into Didi Chuxing for suspected data violations two days after its blockbuster $4.4bn IPO on the New York Stock Exchange in June, forcing the once-dominant ride-hailing company to stop registering new users during the investigation. After the move, the CAC said in July it would tighten rules for companies...